Thermochemical Equation Determine Mass

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The discussion focuses on calculating the mass of copper produced from the thermochemical equation 2Cu2O(s) → 4Cu(s) + O2, with a ΔH of +333.8 kJ/mol. The user initially miscalculated the mass by dividing the total energy consumed (1.47 x 104 kJ) by the enthalpy change per mole of copper instead of per mole of reaction. The correct calculation involves recognizing that 333.8 kJ corresponds to the reaction producing 4 moles of copper, leading to a final mass of 11.2 kg of copper produced.

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disneychannel
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So I am doing practice problems from the textbook and it states:

Given the thermochemical equation: 2Cu2O(s) → 4Cu(s) + O2, ΔH =+333.8 kJ/mol, calculate the mass of copper produced when 1.47 x 104 kJ is consumed in this reaction

My attempt

(1.47 x 104 kJ)/(33.8 kJ/mol )= 44 mol x 2 2 60=5.284 kg
BUT This is wrong and I don't know why...the answer is 11.2 kg
 
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No idea what you did, what is "2 2 60"?

It is 333.8 kJ per "mole of reaction", not "mole of copper".
 

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